Difference between revisions of "How to reduce power consumption"

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(Sound)
(Sound: moved to separate page)
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===Sound===
 
===Sound===
Consumes about 0.3W. Disable by unloading modules or {{cmdroot|echo -n 3 >  /sys/class/sound/controlC0/device/power/state}} (replace 3 by 0 to enable again).
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Consumes about 0.3W.
 
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* [[How to enable AC97 power saving]]
There's a [http://www.kernel.org/git/?p=linux/kernel/git/perex/alsa.git;a=commitdiff_plain;h=6dbe662874ba08585eaf732d126762c25ac8e3f7;hp=2b29b13c5794f648cd5e839796496704d787f5a6 experimental patch] which enables the support
 
of aggressive AC97 power-saving mode.  In this mode, the AC97 powerdown register bits are dynamically controlled at each open/close of PCM streams. The mode is disabled by default, and activated via <tt>power_save=1</tt> option for <tt>snd-ac97-codec</tt> driver (at run time, use {{cmdroot|echo Y > /sys/module/snd_ac97_codec/parameters/power_sav}}). To allow powering off the analog mixer, make sure all analog inputs (Line, Microphone, CD, etc.) are muted.
 
  
 
==Related toptics==
 
==Related toptics==

Revision as of 21:31, 7 October 2006

Reducing system power consumption will extend battery life, reduce system temperature and (on some models) reduce system fan noise. This page summarizes the known techniques for reducing power consumption on ThinkPad laptops under Linux. The power numbers given (in Watt) are very rough and model-specific.

System power states

CPU

Graphics

Hard disk

Spinning down the disk saves about 1W.

Optical drive

The optical drive consumes about 1W even when not accessed.

System fan

Consumes about 0.5W when running.

Wireless network

Consumes up to ~4W.

USB

Causes significant power draw due to bus mastering (affects CPU C-state). Disable by unloading modules, or unbinding the devices in sysfs.

Sound

Consumes about 0.3W.

Related toptics

External resources